High-speed radiotransmitter



May 15,1928. 1,669,502

A. L. WILSON HIGH SPEED RADIOTRANSMITTER Filed Dec. 1.3, 1922 -I WITNEssEs: Ff? 5' f4 f/z. *h

INVENTOR jg MWL. w//SO f 9 BY AToRNEY Patented May 15, 1928.

Y UNITED STATES PATENT* `ARTHUR; L. WILSON, 0F HAMMOND, INDIANA, ASSIGNOR TO WESTlNGI-IOUSE ELECTRIC 6v MANUFACTURING (IIOIVJIZEANY,y CORPORATION OF PENNSYLVANIA.

HIGH-SPEED RADIOTRANSMITTER.

Application filed December 13, 192,2. Serial No. 606,558.

My invention relates to control systems, having particular relation to high-speed automatic radio transmission systems.

The principal object of my invention is to provide a system of the class described, wherein relatively slow-speed circuit-interrupting devices designed to handle heavy currents and high voltages are employed` the signaling speed of the combination oi devices being greater than that oli a single interrupting` device alone.

In the present state ol the art, the relays employed in the usual signal-control systems are required to control relatively heavy currents of high voltages, thereby. necessitating the use of extremely rugged relays having; large braking distances. Such relays, by reason of the heavy construction` of thel mpving parts, are inherently sloyv in operation and thus are unadapted for high-speed sig;- nal-control systems.

I have tounchhoivever, that by operating,l aplurality of relays-in a circuit in such manner that the operating period o one relay overlaps that of another for a predetermined interval, the Icircuit may he interrupted at rate greater than is possible by .the .use .Ot a single unit alone.

lNith these and wothc-ir objects and appli-l cations in view, my invention 'further cionsists in `the arrangement and in the mode ot operation hereinafter set forth and illustrated in the accompanying drawing, Wherein: d

Figures l and 2 are curve diagrams, for dirlferent operating speeds, illustrating the Operating cha aeteristics of a circuit-interrup-,tingn device such is employed in my invention,

F S is a similar view, illustratingy the sequence oi operation of a number ot relays. according to my invention, l

Fig l is adiaggranim "c ,vieiv ,of ciucuits and' apparatus for carryng` my invention into eli'ect, and

Fig. .5 is a top plan view Aof a punched tape which is shown `edzeunvise in the precedv ing ligure.

In. order to illustrate ,the principles Vand applications of my invention, I shall de scribe, hereinafter, ,one arrangement ,ot Acircuits and 4apparatus for kcarrying the same inte practice, .though rit is to lie ACrispi.'essly understood. that my invention is not specilically limited thereto.

rlhe ordinary type of prior-art relay de signed, particularly tor operation inconnecf tion with Wireless control systems, has a maximum operating speed of approximately forty ivords per minute. As previously pointed out, such relatively low maximum operating,l speed is the result ot' the employment of heavy, rugged relays, wherein the movable contact-bearing Aarms traverse relatively long paths. Assuming radio-telegraph signals of ten-dot spaces per letter and lifty-,dot spaces per vvord of live letters each and a speed of transmission ol 'forty Words per minute, the duration of a. dot space is approximately 0.03 of a second, as indicated by the tull-,line'curve ain Fig. 1. The curve a shows the'desi'red position of the relay andthe curve b -showsthe actual movement ot' the relay. In ,each curve the ordinates indica-te position and the abscissze time. The time necessary for,A such relay to closeis approiimatelyy @.Ql of a' second andthe time necessary for therelay to come to rest after separation of its contacts isr also appresimately O .()l of a second Thus, the actual time during which the relay contacts are closed is approximately 0.02 of a second, as indicated by the dotted-line curve o in 1.

the saine relay` is operatedat `-l'our times its normal speed, the. relay contacts would never close, since Ethe relay would be dfi-energized before the eontactsivould haveclosed, indicated in Fig. 2, Where the lull-line curve c .illustrates the desired interval or so-cal'led dot-spaceduring which the relay cont-acts are to be closed and the dottedline curve d illustrates the actual movement, shovving the tin/ Le during' which the relay is energized and d ti-iergizcd.

is .previously stated, lhave discovered that, by employing a plurality o'l relays in a circuit and so operating` them that the operating period `of one relay overlaps that et another, a signaling syst-ein oi'. extremely high speed may be vobtained wherein the individual units .operate at their normal operating; speed. Y

In Fig. 3 is shovvn` operating characteristic curvese and f tor a pair of relays having the previously mentioned `y characteristics, illustrati-ng the overlapping sequence ot oploo eration thereof, whereby signaling may be effected at a speed four times greater than is possible by the use of a single relay alone.

It will be noted that the relay corresponding tov curve f is energized, at times, whilethe Y will appear more fully hereinafter.

The system of control `shown in Fig. 4 is merely` one arrangement for causing a pair ofrelays or circuiteinterruptinf devicesto 'operate-in the manner indicate in Fig. The system therein shown comprises a pair of parallel connected relays 1 andfZ` having stationary Contact elementsB, 3 and 4, 4, and co-operating movable contact elements 5 and 6, respectively, said relays being serially included in a portion 7 of `a radio control system. Since the remaining portions of the control system are not essential to a clear:understanding of the operation of my invention, they have been omitted?. The switch units or relays land 2 are primarily 'controlledby the relative spacings of the perforations in a `pair of tapes 8 and 9, ref spectively, as hereinafter explained.

The `unpunched` tapes may be placed through an automatic punching machine of any Well-known type and provided with series of punchings 11,` 12, and 13, 14 for controlling the relays 1 and2, respectively, and

' af series ofsocalled star-wheel punchings 15, 16. ln order to illustrate the Successive overlapping operation of the relays 41 and 2, as denned by the curvediagram `of Fig. 3, Ihave shown, in Fig. 5, the tapes 8 and 9 with `their several punchings arranged in the proper relative phase relation. The distance g and hseparatingltlie perforations 11 and 12 and g" and 7L separating the perforations 13 and 14, illustrate the time interval between the instant when the relays 1 and 2 are energized and the instant when the relay` contacts are separated, respectively.

In order to siniplify'the descriptionof my invention, the mechanism for.` causing the operation of, say relay 1, `in accordance with the perforations in thetape8 only will be shown and described, the mechanism employed in connection with relay 2 for accomplishing this result being mere duplication. Referring to the mechanism associated with relay 1, the tape 8 may be actuated `by vmeans of arms 17 of a lstai' wheel 18 successively engaging `said star-wheel perforations 15, the star wheel 18 being moved at a uniform speed by means `of a motor (not shown). The rotative motion ofthe star wheel`18 may be caused toeffect the oscillation cfa centrally pivot'ed rocker arm 19`through a crank and connecting rod 21 and`22, respec tively. e i

vThe rocker arm 19 is provided with a. pair of pins 23 and 24 disposed upon-opposite sides of the center of oscillation thereof and coaictiiig with arms 25 and 26 of bell-crank mechanisms 27 and 28, respectively, to cause corresponding vibration thereof. The bellcrank mechanisms 27 and are pivotally mountedabouththe points 29 and 31, respectively. Springs 32 and 33, whicli'are secured to arms 34'a1id 35 of the mechanisms, serve to maintain the arms 25 and 26 thereof in continuous engagement-with their operating pins 23 and 24,respectively` `The ends of the arms 25 and 26 are `connected tovertically positioned rods 36 andtl which are spaced from one another:` the same distance as the perforations 11 and12*of the `tape'.

The rods 36 antl37 are of such length that, when therocker arm 19 is *vibrated `by the crank 21, the ends of the rods alternately press against the lower surface of the tape 8 and extend throughtlie respective perfora`` tions 11 when the tapey is incved forwardby the star vvlieel1-8gto` such position `as `to place a perforation directly'over the end of the `rod which` is being actuatedinto Vcontact with the tape 8. f Thus, the motion of the rodst and 37,heyond an engagement with the lower surface of the taper8, is de-` termined by the relative spacing` ofthe per.-

forations 11 and 12. The rods and-37 are normally maintained in `a vertical position during non-engagement with the perforations l1 and l2 by means of spring inembers 36 and 37 and co-operating stop meni-` bers 36 and 37, respectively, all `asex` plained `more fully hereinafter.

A pivotally'mounted member`38 is provided with oppositely` extending arms `39 and 41 perforated to removably `receive the end portions of a pair of connecting links 42 and `43 extending, respectively, to the arm 34 of the mechanism 27 andto an extension 44 of the arm 35 ofthe mechanism 28. The pivoted member 38 carries a! contact mem` ber 45 which co-acts with a stationary-contact member `46. The endportions of the connecting links 42 and 43 are provided with stops'47and 48, which are so disposed that, when the ends of the rods 36 and 37 merely engage the lower side` of the tape 8, the end portions of the connecting links 42 and `43 merely move back and "forth in the perfo` rated portions of the arms 39 and 41, respectively, vvitho'ut disturbing the relative posi# tions of the contact members '45 and 46.`

e 'When the tape 8 v is advanced by thel star Wheel `18 to the position indicated in thetig-` ure and the end of the arm 37 is caused `to l link 43 moved Vforward an additional amount. Theadditional motion of thelink 43 causes the stop 48 to engage the 'arm 41 i of the member 38 and to move the samesuiciently to actuate the movable contact member or pin 45 into engagement with the stationary contact member 46, all as shown in the drawing.

Vhen the contact members 45 and 46 are actuated into engagement, a circuit is completed through a source 4,9 ot direct-current energy and an energizing winding 51 of the relay 1, to eiiect the operation thereof and the closing of the portion 7 of the control circuit.

Subsequent motion ot the star wheel 18 withdraws the end of the arm 37 :from the perforation 11 and tinally advances the tape 8 to a position where one of the perforations 12 is directly over the end of the rod 36; whereupon the rod 36 is caused to extend up through said perforation. The connecting link 42 is then moved- 'forward an additional amount, causing the stop member 47 to engage the projecting arm 39 and to move the same sufficiently to actuate the two contact members 45 and 46 out of engagement.k

When the two contact members 45 and 46 are disengaged, the energizing circuit of the relay 1 is brolren and it opens to interrupt the portion 'i' of the control circuit. Attention is directed to the fact that the contact members 45 and 46 remain closed during the interval between the projection of the arm 37 through the perforation 11 and the projection of the arm 36 through the perforation 12.

When the tape 8 is again moved forward, the operation of the star wheel 18 and the foregoing mechanical operations are repeated. Thus, it is seen that, as the tape 8 moves forward under the operation of the star wheel 1S, the portion 5 of the control circuit is opened vand closed for a period of time proportional to the interval between the successive projections of the arms 37 and 36 through the perforations 11 and 12, respectively.

The second relay 2 may have its energizing winding 52 connected, through the energy source 49, to the relatively movable contact members 45 and 46 of a circuitinterrupting mechanism (not shown) which is like that just described in connection with the relay 1. Aspreviously stated, in order to simplify the description of my invention, such mechanism is not shown.` The relative arrangement o'f the perforations in the two tapes 8 and 9, as shown in Fig. 5, is such as to cause the operation of the relays 1 and 2 according to the predetermined sequence shown in Fig. 3.

Hence, by the operation of the relays 1 and 2 in the manner just described, the portion 7 of the control circuit may be opened at least four times the normal operating speed of a single relay. Further increases in the speed of: interruption of the portion 5 of the control circuit obviously may be effected' by the addition o more relays, arranging the operating periods thereof to overlap a predetermined amount.

lhile f have shown but one embodiment of my invention, for the purpose of describing the same and illustrating its `principles of' operation, it is apparent that various changes and modifications may be made in the nature and the mode of `operation and the particular mechanism employed without departing from the spirit of my invention. 1 desire thereto-re, that only such limitations shall be imposed thereon as are indicated' in the appended claims or demanded by the prior art.

l claim as 'my invention: j

1. 1n an electrical system, a circuit including a plurality oficircuit-interrupting units and separate actuating means for each ot' said units said actuating means acting in combination in such manner as to cause the interruption ot said circuit at alfrequency greater than that obtainable by the operation of a single unit alone.

2. In a control system, the combination with an electrical circuit, of a plurality of circuit-interrupting devices included therein, said devices requiring a definite time to maire electrical contact and a definite time to return to their initial state after breaking electrical contact, and means for causing the closing period ot' one device and the breaking period et another device to overlap.

3. In a control system, the combination with an electrical circuit, ot' a plurality ot switch units included in parallel in circuit therewith, said units having a. definite time interval in which to open and to close, and means for causing the opening time interval of one unit to overlap the closing time interval oi another unit a predetermined amount.

4. In a control system, the combination Vwith an electrical circuit, of a. plurality ot switching units included in said circuit, said units requiring a definite time interval in whch to open and to close, and means for operating said units in such manner thatJ the operation of one switch is started prior to the discontinuance of operation olA a. preceding switch.

5. n a-control system, the combination with an electrical circuit, o i a plurality of switching units included in said circuit, said units requiring a. definite time interval in which to open and to close, and means f'or operating saidv units in such manner that the time interval between the successive operations or' said switch units is that corresponding to the time interval during which one switch remains closed.

G. In combination, an electrical circuit, a plurality ot relays the contacts of whichfare included therein, said relays having movable circuit-interrupting members requiring a definite time interval to close said circuit ll'lil and a definite time interval toeomefto Irest after interrupting said y circuit land means for securing `the operation of said relays suecee'eively in suoli' manner that Said time intervals everlap. Y

7. In combination, an' electrical `circuit, a plurality or' relays the contarte of which are ix'ieluded tht-nein,` said relayshaying movable circuit-interiupting members requiring deli nite tiineintervals to el'ose Said circuit and to `eoine to rest' after interrupting said eireuit andu means for so energizing' saidl relays ae toV cause Said* opening` time interval of one relay to overlap said closing time interval of a preceding'- relay by a predetermined amount. y

`8. In `a signaling system, the'eoinhination with a Circuit carrying electrical energy, of means for interrunting said circuit to form dots and dashes, said means oomprieing a plurality of relays liaif'ingensuit-interrupting 'members included in parallel in `said circuit andineans for so energizing said relays that the operating period et one relay overlapethatof another a predetermined amount to determine the interval between euceeesive dots.` f y p 9. In a signaling' System, a circuit Carrying electrica-l energy to bev modulated, av plurality ot Switching units included in Said circuit, means individual to each unit for causing the operation ^`thereof;` and means for Causing the operation ot' Said unite in lcombination in suelr manner that the fre-` quency of interruption of the circuit bysdaid vCombination iegreater than that resulting` from one sing-le unit alom-3.` p y u f l0. The method of signaling n'liiehrcon- Sistsjin Succeseively operatinga plurality of circuit-int`erruptingunits inv Such ma.u 

